// 时间戳的处理
// 时间格式处理
function toDateString (d, format){
    var date = new Date(d || new Date())
        ,ymd = [
        this.digit(date.getFullYear(), 4)
        ,this.digit(date.getMonth() + 1)
        ,this.digit(date.getDate())
    ]
        ,hms = [
        this.digit(date.getHours())
        ,this.digit(date.getMinutes())
        ,this.digit(date.getSeconds())
    ];

    format = format || 'yyyy-MM-dd HH:mm:ss';

    return format.replace(/yyyy/g, ymd[0])
        .replace(/MM/g, ymd[1])
        .replace(/dd/g, ymd[2])
        .replace(/HH/g, hms[0])
        .replace(/mm/g, hms[1])
        .replace(/ss/g, hms[2]);
};

//数字前置补零
function digit (num, length, end){
    var str = '';
    num = String(num);
    length = length || 2;
    for(var i = num.length; i < length; i++){
        str += '0';
    }
    return num < Math.pow(10, length) ? str + (num|0) : num;
};
